import cv2
import copy
import numpy as np
import dbnet_crnn.tools.utility as utility
from service.image_utils import get_center_pos
import dbnet_crnn.tools.predict_det as predict_det
import dbnet_crnn.tools.predict_rec as predict_rec


def sorted_boxes(dt_boxes):
    """
    Sort text boxes in order from top to bottom, left to right
    args:
        dt_boxes(array):detected text boxes with shape [4, 2]
    return:
        sorted boxes(array) with shape [4, 2]
    """
    num_boxes = dt_boxes.shape[0]
    sorted_boxes = sorted(dt_boxes, key=lambda x: (x[0][1], x[0][0]))
    _boxes = list(sorted_boxes)

    for i in range(num_boxes - 1):
        if abs(_boxes[i+1][0][1] - _boxes[i][0][1]) < 10 and (_boxes[i + 1][0][0] < _boxes[i][0][0]):
            tmp = _boxes[i]
            _boxes[i] = _boxes[i + 1]
            _boxes[i + 1] = tmp
    return _boxes


class ImageText(object):
    def __init__(self):
        args = utility.parse_args()
        self.text_detector = predict_det.TextDetector(args, model_path='dbnet_crnn/modelv1.1/det/')
        self.text_recognizer = predict_rec.TextRecognizer(args, model_path='dbnet_crnn/modelv1.1/rec/')

    def get_rotate_crop_image(self, img, points):
        '''
        img_height, img_width = img.shape[0:2]
        left = int(np.min(points[:, 0]))
        right = int(np.max(points[:, 0]))
        top = int(np.min(points[:, 1]))
        bottom = int(np.max(points[:, 1]))
        img_crop = img[top:bottom, left:right, :].copy()
        points[:, 0] = points[:, 0] - left
        points[:, 1] = points[:, 1] - top
        '''
        img_crop_width = int(
            max(
                np.linalg.norm(points[0] - points[1]),
                np.linalg.norm(points[2] - points[3])))
        img_crop_height = int(
            max(
                np.linalg.norm(points[0] - points[3]),
                np.linalg.norm(points[1] - points[2])))
        pts_std = np.float32([[0, 0], [img_crop_width, 0],
                              [img_crop_width, img_crop_height],
                              [0, img_crop_height]])
        M = cv2.getPerspectiveTransform(points, pts_std)
        dst_img = cv2.warpPerspective(img, M, (img_crop_width, img_crop_height),
                                      borderMode=cv2.BORDER_REPLICATE,
                                      flags=cv2.INTER_CUBIC)
        dst_img_height, dst_img_width = dst_img.shape[0:2]
        if dst_img_height * 1.0 / dst_img_width >= 1.5:
            dst_img = np.rot90(dst_img)
        return dst_img

    def get_ocr(self, img, max_side_len):
        ori_im = img.copy()
        dt_boxes = self.text_detector(img, max_side_len)
        if dt_boxes is None:
            return None, None
        img_crop_list = []
        dt_boxes = sorted_boxes(dt_boxes)
        for bno in range(len(dt_boxes)):
            tmp_box = copy.deepcopy(dt_boxes[bno])
            img_crop = self.get_rotate_crop_image(ori_im, tmp_box)
            img_crop_list.append(img_crop)
        rec_res = self.text_recognizer(img_crop_list)
        return dt_boxes, rec_res

    def get_text(self, img, max_side_len, score_thresh=0.6):
        result = []
        dt_boxes, rec_res = self.get_ocr(img, max_side_len)
        for roi_ocr in list(zip(dt_boxes, rec_res)):
            roi_score = roi_ocr[1][1]
            if roi_score > score_thresh:
                boxes = roi_ocr[0]
                result.append({
                    'pos': get_center_pos(roi_ocr[0]),
                    'text': roi_ocr[1][0],
                    'score': round(float(roi_score), 2),
                    'elem_det_region': [boxes[0][0], boxes[0][1], boxes[2][0], boxes[2][1]]
                })
        return result


image_text = ImageText()
